Rotary brush comprising an annular bristle carrier and a circle of bristles



4, 1964 A. 'r. NIELSEN ROTARY BRUSH COMPRISING AN ANNULAR BRISTLECARRIER AND A CIRCLE OF BRISTLES Filed March 12, 1965 INVENTOR AI berThaodora [Vie/5e n BYJMNM ATTORNEYS 4, 1964 A. T. NIELSEN 3,142,854

ROTARY BRUSH COMPRISING AN ANNULAR BRISTLE CARRIER AND A CIRCLE 0FBRISTLES Filed March 12, 1963 2 Sheets-Sheet 2 INVENTOR Hlbev'l TheodoraNialsen ATTORNEYS United States Patent ice RQTARY BRUSH COMPRISING ANANNULAR BRISTLE CARRIER AND A CIRCLE @F BRISTLES Albert TheodoreNielsen, Nr. Biaert, near Kolding, Denmark, assignor of one-half toNiels Edward Nielsen, Kolding, Denmark Filed Mar. 12, 1963, Ser. No.264,491 Claims priority, application Denmark Mar. 15, 1962 1 Claim. (Cl.15-180) In known rotary brushes comprising an annular bristle carrierand a circle of bristles arranged in tufts, these tufts are as a ruleinserted into sockets in the bristle carrier and secured by means ofstaples or a wire in connection with pitch. This method of attachmentassumes in practice that the bristle carrier has a considerablethickness, and in great brushes, for example for street sweepers, thecarrier will become correspondingly heavy and unhandy. This method is,therefore, not compatible with modern efforts which go in the directionof making the bristle carrier so light and cheap as to make iteconomically justifiable to discard the bristle carrier when thebristles attached thereto have been Worn down.

This invention has for its purpose to provide a rotary brush in whichthe advantageous tufted arrangement of the bristles can be employed inconnection with a light and cheap bristle carrier.

From other brush types, for example hair brushes and tooth brushes, itis known to bend a tuft of bristles into hairpin-shape and insert thebent end of the tuft into a thimble-like holder, and it has beensuggested to secure the attachment of the bristles or the brush materialto said holder either by means of a staple which with its centralportion is disposed internally of the bristle bends, and with its limbsis in frictional engagement with the inner side of the holder, or bymeans of a cross pin correspond ing to the central portion of thestaple, this pin being fixedly secured within the holder by means of thefree edge thereof which is reduced in diameter after the insertion ofthe cross pin.

With a view to obtaining the above-mentioned purpose, this priortechnique is utilized in the rotary brush according to the invention,said brush comprising an annular bristle carrier and a circle of brushmaterial in the form of hairpin-shaped bristles which are gathered intufts, the bent end of each of which is inserted into a separate tubularholder and secured therein by means of a wire or pin disposed internallyof the bristle bends. The charactereristic feature of the rotary brushaccording to the invention is that said wire or pin extends throughsubstantial radial, opposed holes in the wall of the holder andcooperates, outside said holder, with the bristle carrier in such manneras to contribute to locking the holder and, conseqently, the tuft in thebristle carrier.

Such wire or pin extending through holes in the wall of the holder willprovide a safer locking of the bristles than the above-mentioned staple,whose effect is dependent on the friction between the limbs of thestaple and the inner side of the holder; and in comparison with theother above-mentioned known construction, the invention affords theadvantage that the locking of the bristles in the holder does notpresuppose any final additional working of said holder, such as therolling-in of the edge portion thereof. Furthermore, the wire or pin inthe rotary brush according to the invention does not only secure theattachment of the brush material in the holder but also locks the holderand, consequently, the tuft in the bristle carrier or at any ratecontributes to this locking. The double employment of the wire or pin isof particularly great significance because hereby it is made possible tomake the bristle carrier simpler and cheaper, and especially to reducethe required thickness thereof.

3,142,854 Patented Aug. 4, 1964 In this connection it can be mentionedthat the above-mentioned known holders comprising a cross pin secured bymeans of the edge of the holder, are externally threaded for beingscrewed into a correspondingly threaded hole in the bristle carrier, forwhich reason said carrier must in practice have a thickness exceedingthe length of the holder.

The production of the individual tufts may by way of example be effectedby a bunch of rectilinear bristles being so disposed transversely of aferrule as to allow the central portion of said bunch of being pressedinto the ferrule, thus attaining the hairpin-shape. The wire or pin forsecuring the brush material in the holder need not to be brought intoplace until later, for example, when the holder with the brush materialis mounted in a bristle carrier.

A particular advvantage in using a Wire or pin extending through holesin the wall of the holder is that the spreading of the bristles in theindividual tufts can be adapted according to wish by choosing anappropriate spacing between the end of the holder Where the bristlesextend therefrom, and the place where the holes are located. The smallerspacing the greater spreading of material. Particularly when thisspacing is small, the tubular holders may according to the inventionadvantageously be substantially cylindrical over a major part of theirlengths and may expand in trumpet-shape at their ends Where the bristlesproject from the holder. This special shape will not complicate theproduction of the holders, and may afford the advantage that the brushmaterial is protected in the best possible way against breaks within theparticularly critical area at the freely-disposed end of the holder.

As emphasized above, the invention affords not only a particularlyreliable attachment of the brush material to the bristle carrier butalso the possibility of producing the said carrier in a simpler andcheaper Way. Thus, in case of a cup-shaped rotary brush, the bristlecarrier may expediently consist of a ring shaped as a fiat truncatedcone and having a circle of through holes for receiving one tubularholder each, the radial holes of which are disposed substantially flushwith the side of the ring tacing away from the brush material. In thiscase a wire or pin which is passed through the radial holesin thebristle carrier and, consequently, secures the brush material therein,will prevent the holder and the brush material from being pulled outfrom the bristle carrier. An oppositely directed displacement of theholder will in ad Vance be precluded if, in the abovementioned manner,the holder is expanded in trumpet-like fashion at the end where thebristles project from the holder.

In a particular embodiment of the cup-shaped brush, two neighbouringholders with associated tufts are secured by means of a single U-shapedwire, the limbs of which are passed through one each of the two holders.Hereby is in a simple manner any turning of the holders in the bristlecarrier prevented, whereby such wear might occur that the holders wouldgradually fit too loosely in the bristle carrier.

The rotary brush may also be in the form of a substantially plane brushring or brush section, the bristle carrier of which has an outwardlyopen groove for reception of the brush material. Such rotary brush isaccording to the invention characteristic in that the cross section ofthe groove is of the same size as the outer diameter of the holder, andthat all holders with associated tufts are secured in the groove bymeans of a circumferentially disposed clamping wire, the ends of whichhave been passed through a hole at the bottom of the groove and fixed,for example, by welding.

Also this rotary brush will be simple and cheap in production and can inspite of low costs of material be produced with fully suflicientstrength. The circumferential clamping wire will together with the sidewalls of the groove normally be capable of retaining the bristle tuftswith required safety but, according to the invention, the holders mayfurther be fixed in the bristle carrier by squeezing the parts of thegroove walls disposed between the holders. Hereby any displacement ofthe individual bristle tufts in the circumferential direction of thebristle carrier is counter-acted, and furthermore the inclination onpart of the tufts to tilt in the groove is counter-acted.

Brush rings or brush sections of the said type are often internallyprovided with a driving stud to ensure the transmission of the rotarymotion from a driving shaft. According to the invention, the ends of theclamping wire may expediently be passed into a tubing located internallyof the groove bottom, which tubing serves as such driving stud for thebrush section.

The invention will in the following be explained in detail through someembodiments with reference to the accompanying drawing, where:

FIGS. 1 and 2 show two sections, at right angles to one another, of abristle tuft comprising holder and locking wire,

FIG. 3 is a section of a cup-shaped brush, viewed from the rear or thetop,

FIG. 4 is a section along line IVIV in FIG. 3,

FIG. 5 is a section of a plane brush ring or brush sec tion comprising acircumferentially disposed locking wire,

FIG. 6 is an edge-view, corresponding to FIG. 5, comprising two holderswithout brush material, shown in section along line VI-VI in FIG. 7, and

FIG. 7 is a section at right angles to the section in FIG. 5 and madebetween two holders as indicated by line VIIVII in FIG. 6.

The bristle tuft shown in FIGS. 1 and 2 consists of a plurality ofhairpin-shaped bristles 1 which may be smooth or crimped steel wires,the bent ends of which have been inserted into a tubular holder in theform of a substantially cylindrical ferrule 2, the lower edge portion ofwhich expands in trumpet-like fashion. A wire or pin 4 is passed throughradial holes in the holder 2 and serve for retaining the bristles 1 insaid holder such as will most clearly appear from FIG. 2.

FIGS. 3 and 4 show a bristle carrier in the form of steel ring 5 shapedas a flat circular truncated cone and having a circle of through holeswhich each receive a tubular holder 2 with brush material 1. As Willappear from FIG. 4, the tufts consisting of the brush material 1 and theholders 2 have been pushed into the ring 5 from the underside thereofuntil the expanded lower edge 3 of the holders engage the underside ofthe ring 5. Now, the radial holes through the holder 2 flush with theupper side of the ring 5, and wires 4' have been passed through theseholes, which wires in the embodiment shown are U-shaped and have theirlimbs passed through one each of two neighbouring holders 2. These Wires4' will prevent the holders 2 from being downwardly pulled out from thering 5 and, moreover, secure the bristles 1 in the holder 2.

A number of flaps 6, FIG. 3, which make it possible to mount thecup-shaped brush in, for example, a street sweeper, may by welding orotherwise be secured to the upper side of the ring 5.

FIGS. 5, 6 and 7 show a brush ring or brush section comprising acircular bristle carrier 7 of U-cross-sectional shape, the bottom ofsaid U-facing the centre of the ring, so that the ring forms anoutwardly open groove for receiving the brush material. This material islike in the preceding embodiment constituted of a plurality of tufts inholders 2, 3. The cross section of the groove is of the same size as theouter diameter of the holders 2, and these holders are located,appropriately interspaced, in the groove of the bristle carrier 7 sothat the rear edges of the holders rest against the bottom of saidgroove. Through radial holes in all holders 2 there is passed a clampingwire 8, the ends of which are inserted into a tubing 9 locatedinternally of the groove bottom and serving as driving stud for thebrush section, and to which the Wire ends may be fixed by welding orotherwise.

For the purpose of further securing the bristle tufts in the bristlecarrier 7, the parts of its side walls disposed between the holders 2may be squeezed such as it is indicated in FIGS. 6 and 7. This has forits particular purpose to ensure that the bristle tufts shall not bedisplaced in the circumferential direction of the bristle carrier 7, andat the same time the inclination on part of the bristle tufts fortilting during use is counter-acted.

A number of brush rings or brush sections of this type may be combinedon a suitable shaft so as to form a drumshaped brush for use in, forexample, a street sweeper.

What is claimed is:

A rotary brush comprising an annular disc shaped brush back memberhaving a circular series of circumferentially spaced holes therein, aplurality of tubular holders inserted through said holes from theexternal surface thereof, said holders having opposed holes therein, aplurality of tufts consisting of bristles of hairpin shape mounted insaid tubular holders, a cross pin extending completely through each ofsaid holders and its opposed openings and extending through the bend ofthe hairpin bristles therein to secure said bristles in said holders andsaid holders in said sockets, said opposed holes being disposed flushwith the internal surface of said annular disc, and wherein the crosspins of two adjacent ristle tuft holders are formed by the limbs of agenerally U-shaped wire.

References Cited in the file of this patent UNITED STATES PATENTS832,805 Osborn Oct. 9, 1906 840,106 Bowditch Jan. 1, 1907 1,125,153Nielson Jan. 19, 1915 2,160,029 Nielsen May 30, 1939 2,267,850 vUshakoifDec. 30, 1941 2,616,111 Vose et al. Nov. 4, 1952 2,907,064 Erickson Oct.6, 1959 FOREIGN PATENTS 16,986 Great Britain Sept. 24, 1900 323,094Germany July 15, 1920 267,015 Italy Aug. 22, 1929 549,722 Germany May 2,1932 754,953 Great Britain Aug. 15, 1956

